Contextual advertising has commonly been implemented for web-based content, such as websites, where targeted advertisements are shown to a specific user or for specific products based on the content shown on the website. The context for the advertisement may greatly impact the success of the advertisement. For example, it is thought that a user may find interest in an advertised product or service that is related to a product or service that the user has previously expressed interest in or purchased, and so the advertisements may be shown to the user based on the user's historical or usage characteristics. Additionally, profiles of users may be developed that indicate a user's personal characteristics, such as age, gender, income, etc., and this information may be used for successfully advertising products or services that are marketed for people with similar characteristics. Further, principles of contextual advertising suggest that advertisements shown to a user that are associated with the content of a website or article being viewed by the user are more effective than advertisements for unrelated products or services.